Theoretical Studies of Gravitational Effects in Chemical Vapor Deposition

1986 ◽  
Vol 87 ◽  
Author(s):  
Charter D. Stinespring ◽  
Charles E. Kolb ◽  
Kurt D. Annen
Keyword(s):  
Chemical Vapor Deposition ◽  
Mass Transport ◽  
Gas Phase ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Large Temperature ◽  
Fluid Properties ◽  
Convective Fluid ◽  
Phase Chemistry

AbstractChemical Vapor Deposition (CVD) processes are generally carried out under large temperature gradients. These gradients, temperature dependent fluid properties, and the earth's gravitational field give rise to buoyancy-driven free convective fluid flow which augments heat and mass transport in the CVD reactor. Under certain conditions, this free convective flow may alter the gas phase chemistry associated with the deposition process. In order to understand these free convective effects and their implications for the deposition process, a computational model describing the combined effects of fluid mechanics and chemistry has been developed. This model uses a coupled chemical equilibrium/mass transport code in conjunction with a 2-D elliptic fluid dynamics code to describe gas phase species profiles and deposition rates. This paper briefly describes the development of the model, its use, and the results of typical calculations.

Computational Study of Reactive Flow in Halide Chemical Vapor Deposition of Silicon Carbide Epitaxial Film

2008 ◽  
Author(s):  
Rong Wang ◽  
Ronghui Ma
Keyword(s):  
Chemical Vapor Deposition ◽  
Gas Phase ◽  
Deposition Rate ◽  
Vapor Deposition ◽  
Computational Study ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Large Temperature ◽  
Processing Conditions ◽  
Wide Range

In this study, a comprehensive transport model is developed for Halide Chemical Vapor Deposition (HCVD) system which includes gas dynamics, heat and mass transfer, gas-phase and surface chemistry, and radio-frequency induction heating. This model addresses transport of multiple chemical species in high temperature environment with large temperature difference and complex chemical reactions in gas-phase and on the deposition surface. Numerical modeling of the deposition process in a horizontal hot-wall reactor using SiCl4/C3H8/H2 as precursors has been performed over a wide range of operational parameters to quantify the effects of processing parameters on the film growth. The simulations of the deposition process provide detailed information on the gas-phase composition as well as the distributions of gas velocity and temperature in the reactor. The deposition rate on the substrate surface is also predicted. The results illustrate that deposition temperature and the flow rate of carrier gas play an important role in determining the processing conditions and deposition rate. A high concentration of HCl exists in the growth chamber and the etching of the SiC films by HCl has significant effect on the deposition rate. The modeling approach can be further used to improve reactor design and optimization of processing conditions.

scholarly journals Gas Phase Chemistry of Trimethylboron in Thermal Chemical Vapor Deposition

2017 ◽  
Vol 121 (47) ◽  
pp. 26465-26471 ◽  
Author(s):  
Mewlude Imam ◽  
Laurent Souqui ◽  
Jan Herritsch ◽  
Andreas Stegmüller ◽  
Carina Höglund ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Gas Phase ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Thermal Chemical Vapor Deposition ◽  
Gas Phase Chemistry ◽  
Phase Chemistry

scholarly journals Methylamines as Nitrogen Precursors in Chemical Vapor Deposition of Gallium Nitride

2018 ◽  
Author(s):  
Karl Rönnby ◽  
Sydney C. Buttera ◽  
Polla Rouf ◽  
Sean Barry ◽  
Lars Ojamäe ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Surface Chemistry ◽  
Gas Phase ◽  
Vapor Deposition ◽  
Electronic Device ◽  
Chemical Vapor ◽  
Group 13 ◽  
Gas Phase Chemistry ◽  
Device Applications ◽  
Phase Chemistry

Chemical vapor deposition (CVD) is one of the most important techniques for depositing thin films of the group 13 nitrides (13-Ns), AlN, GaN, InN and their alloys, for electronic device applications. The standard CVD chemistry for 13-Ns use ammonia as the nitrogen precursor, however, this gives an inefficient CVD chemistry forcing N/13 ratios of 100/1 or more. Here we investigate the hypothesis that replacing the N-H bonds in ammonia with weaker N-C bonds in methylamines will permit better CVD chemistry, allowing lower CVD temperatures and an improved N/13 ratio. Quantum chemical computations shows that while the methylamines have a more reactive gas phase chemistry, ammonia has a more reactive surface chemistry. CVD experiments using methylamines failed to deposit a continuous film, instead micrometer sized gallium droplets were deposited. This study shows that the nitrogen surface chemistry is most likely more important to consider than the gas phase chemistry when searching for better nitrogen precursors for 13-N CVD.

scholarly journals Methylamines as Nitrogen Precursors in Chemical Vapor Deposition of Gallium Nitride

2019 ◽  
Author(s):  
Karl Rönnby ◽  
Sydney C. Buttera ◽  
Polla Rouf ◽  
Sean Barry ◽  
Lars Ojamäe ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Surface Chemistry ◽  
Gas Phase ◽  
Vapor Deposition ◽  
Electronic Device ◽  
Chemical Vapor ◽  
Group 13 ◽  
Gas Phase Chemistry ◽  
Device Applications ◽  
Phase Chemistry

Chemical vapor deposition (CVD) is one of the most important techniques for depositing thin films of the group 13 nitrides (13-Ns), AlN, GaN, InN and their alloys, for electronic device applications. The standard CVD chemistry for 13-Ns use ammonia as the nitrogen precursor, however, this gives an inefficient CVD chemistry forcing N/13 ratios of 100/1 or more. Here we investigate the hypothesis that replacing the N-H bonds in ammonia with weaker N-C bonds in methylamines will permit better CVD chemistry, allowing lower CVD temperatures and an improved N/13 ratio. Quantum chemical computations shows that while the methylamines have a more reactive gas phase chemistry, ammonia has a more reactive surface chemistry. CVD experiments using methylamines failed to deposit a continuous film, instead micrometer sized gallium droplets were deposited. This study shows that the nitrogen surface chemistry is most likely more important to consider than the gas phase chemistry when searching for better nitrogen precursors for 13-N CVD.

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